The present invention relates to a sheet roll assembly for use in cooperation with an apparatus from which sheet material emerges, and more particularly, the invention relates to a receiving and roll assembly for rolling lengthy and cumbersome sheets shuch as original design tracings and/or reproductions emerging from a copying and processing machine, such as a blueprint printing and processing machine and the like.
The present invention has particular applications in copying machines for producing "blueprint" reproductions of a sheet original, such as tracings made on transparent or translucent paper, velum, or mylar bases. Such sheet original tracings are generally of large size and may have considerable length. The copying machine has a forward projecting table disposed below a slot-like opening and the sheet original, disposed above a sheet of duplicating paper treated with a photosensitive material such as diazo paper or the like, is manually introduced in contact with the photosensitive sheet into the machine through the opening. The two sheets are fed in unison by means of appropriate rollers and conveyor belts into the machine to provide exposure of the duplicating paper through the tracing sheet original acting as a photomask. After exposure, the sheet original and the sheet of duplicating paper are separated within the machine and the sheet original is caused to emerge from the machine through an opening generally disposed on the same side of the machine as the inlet opening, while the sheet reproduction is fed, by way of appropriately disposed rollers and conveyor belts, to another section of the machine where it is processed. After processing, the sheet reproduction is fed through an opening to the outside of the machine, such opening being generally disposed on an opposite side of the machine, and is conveyed into a receiving tray or onto a table. The sheet original may also be received into a tray disposed above the table of the machine but is generally allowed to be fed freely through the outlet opening and fall on the table.
From the above description it is readily apparent that the machine operator is faced with many problems. It is difficult for a single operator to handle both the material being fed into the machine and the material emerging from the machine, especially when the material is particularly lengthy. In such case, two operators are generally required, for handling the lengthy material fed into the machine and for manually rolling or folding the material as it emerges from the machine, and long tracings, especially on a mylar or similar base, are relatively heavy, and awkward to handle by a single person. In addition, mylar and velum tracings are generally stored in a rolled condition, and thus must be manually re-rolled while they emerge from the machine or, alternatively, prior to storing.
When handling extremely long sheet originals, the leading edge of the original often emerges from the machine while the trailing edge thereof is still on the table, thus causing entanglements and damages to costly original tracings.
Therefore many advantages result from providing a copying machine, such as a blueprint machine, with a roll mechanism for re-rolling original tracings as they emerge from the machine, automatically and without causing any damage to the costly tracings. As the operator of the machine is no longer required to manually roll the tracings as they emerge or to take the precaution that an emerging tracing does not tangle with the material being fed into the machine, there is no longer any requirement for two operators to be in attendance, there is a considerble reduction of the operator's work load, there is less risk of damaging the tracings, and the tracings are automatically obtained, as they emerge from the machine, in a rolled condition, thus eliminating the manual re-roll operation. If so desired, a sheet roll assembly according to the present invention may also be attached to the machine where the duplicating paper emerges after processing, such that the sheet reproductions are also obtained in spiral rolls.
There have been some attempts, in the past, to provide copying machines with tracing re-roll mechanisms. For example, in U.S. Pat. No. 3,406,921, there is disclosed a re-roll assembly for tracings emerging from a copying machine consisting of a tray having a V-shaped trough-like bottom panel provided with projecting rotating disks. Appropriate feed rollers direct the emerging tracing to the bottom of the trough, where it is rolled up by the rotating disks. Such an arrangement, wherein the tracing surface is engaged with relatively narrow rotating surfaces, may deteriorate the tracing, and requires that the tracing leading edge be directed at the apex of the trough in order for the tracing to be successfully re-rolled. If the leading edge of the tracing engages any portion of the trough other than the apex where the disks are disposed, automatic successful re-rolling of the tracing is not achieved.